A method and system for performing a pre-reserved handover in a mobile communciation system is suggested, wherein an additional handover preparation step is performed by determining at least one candidate base station in advance, to which handover is likely to be performed. An additional downlink connection to the at least one candidate base station is established before handover execution is performed. Thereby, proper handover can be ensured for cell environments in which a serving cell disappears very quickly from a mobile station.